Psoriasis Flashcards
Define psoriasis
Chronic autoimmune disease characterised by well-demarcated, erythematous, scaly plaques
Risk factors for psoriasis development
Family history
HIV infection
Obesity
Smoking
Triggers for psoriasis
Skin trauma (Koebner phenomenon)
Infection: Streptococcus, HIV
Drugs:B-blockers,Anti-malarials,Lithium,Indomethacin/NSAIDs (BALI)
Withdrawal of steroids
Stress
Alcohol + smoking
Cold/dry weather
Types of psoriasis
Chronic plaque psoriasis (most common)
Flexural (inverse) psoriasis
Guttate psoriasis
Pustular psoriasis
Generalised/erythrodermic psoriasis
Clinical features of chronic plaque psoriasis
Itchy, well-demarcated circular-to-oval bright red/pink elevated lesions
Overlying white or silvery scale
Distributed symmetrically over extensor body surfaces and scalp
Nail signs: pitting, onycholysis, subungal hyperkeratosis
Arthritis
Clinical features of flexural (inverse) psoriasis
Smooth, erythematous plaques without scale in flexures and skin folds
Clinical features of guttate psoriasis
Multiple small, tear-drop shaped, erythematous plaques occur on the trunk
Occur after a Streptococcal infection in young adults
Clinical features of pustular psoriasis
Multiple petechiae and pustules on the palms and soles
Topical treatment for psoriasis
Emollient to reduce scale and itch
1st: potent topical corticosteroid OD (e.g. Betnovate) + topical vitamin D OD (e.g. Dovonex) applied at different times
2nd: stop the topical corticosteroid, apply topical vitamin D twice daily
3rd: stop the topical vitamin D, apply potent topical corticosteroid twice daily
Dithranol + tar are alternatives
Phototherapy for psoriasis
1st: narrowband UVB phototherapy
2nd: psoralen + UVA (PUVA)
Systemic treatment for psoriasis
1st: methotrexate
2nd: ciclosporin
3rd: acitretin
Systemic retinoids
Biologic treatment for psoriasis
Infliximab
Etanercept
Adalimumab
Complications of psoriasis
Psoriatic arthropathy (around 10%)
Increased incidence of metabolic syndrome
Increased incidence of cardiovascular disease
Increased incidence of venous thromboembolism
Psychological distress
Complications of systemic therapies used in psoriasis
Methotrexate can cause pneumonitis and hepatotoxicity (monitor LFTs).
Methotrexate may cause myelosuppression leading to pancytopenia (monitor FBCs)
Acitretin is teratogenic and can cause hepatotoxicity and elevated lipids
Anti-TNF biological drugs (such as adalimumab) are associated with reactivation of latent tuberculosis
Potency of topical steroids
HelpEveryBuddingDermatologist”
Mild-Hydrocortisone 0.5%
Moderate-Eumovate (clobetasone butyrate 0.05%)
Potent-Betnovate (betamethasone valerate 0.1%)
Very potent- Dermovate (clobetasol propionate 0.05%)
